1. Field of the Invention
The invention relates to an AC-DC converter which uses an AC power source, particularly a commercial AC power source as an input and which supplies a DC voltage at a high power factor.
2. Description of Prior Art
An AC-DC converter of the prior art is disclosed in U.S. Pat. No. 5,019,952.
A prior art converter having such a configuration allows an input current to have a sinusoidal waveform including harmonic currents of reduced levels. In order to shape the waveform of an input voltage, however, the converter requires a circuit for detecting an input AC voltage, and a multiplying circuit, and hence has a problem in that the circuit scale is enlarged.